Hammer for impact crushers with detachable and reversible hammer head



Feb. 1, 1949. 4, a. EH 2,460,279-

- HAMMER FOR IMPACT cnusnsns WITH DETACHABLE AND REVERSIBLE HAMMER HEADFiled D00. 10, 1943 3 Sheets-Sheet l LE \E q. 2-H

L' G. EHMANN HAMMER FOR IMPA CT CRUSHERS WITH DETACHABLE AND REVERSIBLEHAMMER HEAD Filed Dec. 10, 1943 3 Sheets-Sheet 2 TERA 5% Feb. 1, 1949.L. G. EHMANN 2,460,279

HAMMER FOR IMPACT CRUSHERS WITH DETACHABLE 3 Sheets-Sheet 3 ANDREVERSIBLE HAMMER HEAD Filed Dec. 10, 1943 jg; 5. J2

UNITED STATES PATENT OFFICE HAMMER FOR IMPACT CRUSHERS WITHIIJIETACHABLE AND REVERSIBLE HAMMER Leslie G. Ehmann, Portland, reg.,assignor to Electric Steel Foundry, Portland, 0reg., a corporation oiOregon Application December 10, 1943, Serial No. 513,759

10 Claims.

This invention relates to rotary impact crushers of the type commonlyused to crush or pulverize rock, coal, cement and similar substances,and.

more specifically to a new and improved hammer tached from the shankduring operation of the crusher.

A further object of the invention is to provide a reversible type hammerhead so constructed as forusgtherein, to provide for a maximum amount ofsurface Rotary impact crushers usuall comprise a rotor wear beforenecessitating replacement. element mounted within a generall cylindricalThese and other features-of the invention are cage formed of breakerbars, said rotor element fully described in the following paragraphs,refcomprising a plurality of discs mounted in spaced erence being madeto theaccompanying drawings relation on a driven shaft and having aplurality in which: of hammers pivotally attached to the rotor eie-Figure 1 is an end view of the rotor element of ment adjacent theperiphery of the discs. The a rotary crusher showing the relativepositions of rotor element is driven at high speed and material fourrows of hammers of a type embodying the fed thereto is crushed orpulverized between the present invention; Figure 2 is a longitudinalview, hammers and the cage. Each row of hammers approximately on theline 2-2 of Figure 1, of a usually is attached to the rotor element bymeans portion of a crusher illustrating the arrangement of a singlepivot shaft extending through openof a row of hammers therein; Figure 3is a perings near the periphery of the discs, with the p i e View, p r yn i n, of a hammer hammers mounted on the shaft between the discs. ead;ig 4 is a p spe tive view of a hammer Impact hammers embodying thepresent inshank s owi t e locking p n b ng assembled; vention areadapted for use in various types and Fi re 5 i a fragm ntary sectionalview of a kinds of crushers and reducers, the leading edges hammer shankshowing the manner in which the of the hammers being subject toconsiderable wear h for admitting e locking p is Closed p under impactwith the material being crushed. man ntly aft r as m ly t p n sp m nt Itbecomes desirable, therefore, to periodically ref h p Figure 6 is aperspective view, partly verse the position of the head on the shank toin section, of a hammer embodying the present provide for more even wearof the hammer head, i ve ust ating the same as being mounted and toreplace the head portion entirely when in Working p t 0n the Pivot s a tof a rotary worn to such an extent as to make further use crusher;Figure 7 is a pe p View, P y in impractical. w t t various types ofhammers section, similar to Figure 6, showing the manner in useheretofore it has been necessary to remove cking the hammer head fromthe shank the pivot shaft from the rotor element in order to. forreversing replacing the same Without disreverse or replace the headportion of the hamassembling the shank from the pivot shaft; and mer.This operation requires the dismantling of Figures 8v and 9 illustrate asectional elevation of aconsiderable portion of the machinery comprisahammer showing a modified construction eming the rotor element, and isthe cause of conbodying the invention and the manner of siderable delaysin the operation of the crusher, locking the hammer head and usflallyl'eqlm'es the use P special tools- In Figures 1 and 2 is shown portionsof a rotor In the b an oblect ofthe present element such as used in acrusher of conventional nvention 15 to provide a hammer adapted for use40 design The rotor comprises a driven shaft '0 1n rotary impactcrushers, of which-the head por- .havin a 1 rt f I tion may be reversedor replaced in a minimum g p um I y o lscs mounted. thereon and keyedthereto each of the several discs havlength of time wlthout the use ofspecial tools 1 and without detaching the shank portion of the mg aiuanyextgndmg hubrmwns by reason hammer from the shaft which connects it tothe of which the dlscs are posltioned on the i rotor assembly. spacedapart relation. Each disc is provided A further object of the inventionis to provide afiiacent its Periphery with Openings '3 spaced areversible type hammer head which may be so ninety degrees apart forreception therethrough attached to the shank portion that none of the ofPivot shafts on Whieh are mounted the stresses imposed upon the head areimparted to Shanks of a plurality of hammers embodying t fastening meansI v the instant invention. The hammers are mount- It is a further objectof the invention to provide ed between each adjacent two of the discs II the a. reversible type hammer head which may be s an s extendingbetween the discs for eng detachably secured to the shank portion insuch 56 ment with the pivot shafts I4. Each of the manner as to precludethe head becoming deshanks I5 is provided with an eye It for receivingtherethrough the pivot shaft ll by which the hammer is secured to therotor element.

Each of the hammers comprises a shank portion I 3 for attachment to therotor element in the manner above described, and a head portion 2|detachably fastened to the shank portion by a locking device presentlyto be described. The shank portion I is of one piece construction andcomprises an elongated body of generally rectangular shape having at oneend thereof an eye I8 for the reception of the pivot shaft I4 andprovided at the opposite end thereof with an elongated slot ll extendingtransversely through the outer end l8 of the shank, the axis of the slotill being parallel with the axis of the eye i8. The shank I5 is formedwith an enlargement intermediate its ends providing shoulders I8encircling opposite edges of the shank and facing in the direction ofthe slotted outer end |8 for insuring a proper seating relation betweenthe head 2| and the shank I5. The outer end l8 of the shank forms aprojection extending outwardly from the shoulders i9 and is adapted tobe received in a recess 26 in the hammer head 2|.

A bore 22 is provided longitudinally of the shank l5, and mounted withinthe bore 22 and having free movement longitudinally thereof is a lockingpin 28. At the outer end of the shank the bore 22 opens into the slotll, while at the inner end of the shank the bore 22 opens into the eye66. The locking pin 23 is made somewhat longer than the length of thebore 22 and projects either into the slot il or into the eye it, as thecase may be. The locking pin 23 is not of sufficient length,.however, toproject into both the slot il and the eye l6, so that when the end ofthe pin projects into the slot ii, for example, the opposite end of thepin is received into the body of the shank.

The hammer head 2| comprises a work performing portion 24 positionedaway from the shank, and a shank end receivin portion 25 positionedtoward the shank and having a central open recess 26 within said shankend receiving portion of such size as to receive therein the slotted end|8 of the shank, whereby the several parts may be assembled into oneoperating unit. In the construction illustrated in the drawings, therecess 26 is defined by end walls 21 and side walls 28. The walls 21 and28 terminate in shoulders 29 which lie in the plane of the inner surfaceof the hammer head and cooperate with the shoulders I9 on the shank IEto prevent a rocking motion between the shank I5 and the head 2| when inoperation. The side walls 23 of'the recess 25 in the hammer head areprovided with aligned slots 3| which, when the shank I5 and head 2| areassembled, are in alignment with the slot I! in the end portion |8 ofthe shank, thus providing a continuous opening extending entirelythrough the hammer head 2 I. An advantage of this construction lies inthe fact that the recess 26 in the hammer head may be relativelyshallow, as compared to the work performing portion 24 of the head, andso provides a maximum amount of wearing surface, which reduces operatingcosts by reason of the longer use of the head before replacement isnecessary.

' For lockin the hammer head 2| on the end of the shank I 5 there isprovided a key 32 of such shape as to conform to the opening through thehammer head formed by thealigned slots 3| and I! when the hammer headand shank are in assembled relation. The key 32 is provided with athrough hole 33 which, when the key is 7 within.

in proper position, is in alignment with the longitudinal bore 22 in theshank I! in which is mounted the locking pin 23. When the key 32 isinserted in the aligned slots 3| and I! the locking pin 23 drops intothe through hole 33 in the key and prevents displacement of the key fromthe aligned slots. In that embodiment of the invention illustrated inFigures 6 and 'I the locking pin 23 is of such length that when theouter end thereof is in engagement with the key 32 the inner end of thepin is flush with the peripheral wall surface of the eye i6 so that thepresence of the pivot shaft M, by which the hammers are secured to therotor element of the crushin device, prevents longitudinal movement ofthe locking pin in the bore 22, thus insuring against displacement ofthe key 32. The key, in turn, securely locks the hammer head 2| to theshank i5 and prevents any of the parts becoming displaced duringoperation of the crusher.

The shank i5 is provided with a transverse bore 3% communicating withthe longitudinal bore 22 which provides access to the locking pin 23 inthe event accumulations of material in the bore 22 may require manualeffort to move the pin.

In Figures 4 and 5 is illustrated the manner of assembling the lockingpin 23 in the longitudinal bore 22. When the shank i5 is cast the bore22 is made to extend through the end l8 of the shank, i. e., through theportion forming the outer wall of the transverse slot ll. Thereupon thelockin pin 23 is placed in the longitudinal bore 22 and the opening inthe end of the shank is permanently closed as by welding a plug 30there- The locking pin is of lesser diameter than the diameter of thebore 22 and has free movement longitudinally therein, the pin beingretained in the bore by the plug 30 at the outer end of the shank and bythat portion of the inner end of the shank forming the wall of the eyeI6.

Figures 6 and 7 illustrate a construction in which the pivot shaft l4,extending longitudinally of the rotor element through aligned openingsl3 in spaced discs H, is provided with notches 35 which are spacedlongitudinally of the shaft a distance corresponding to the distancebetween the locking pins 23 in adjacent hammers. Each notch 35 is ofsufilcient size to receive therewithin the end of a locking pin 23, andis of such depth that when the inner end of the locking pin 23 dropsinto the notch 35 the opposite end of the locking pin disengages the key32, permitting the keyto be removed from the hammer head to permitremoval of the head from the shank.

In assembling the hammers in the crusher, each row of hammers is mountedon the rotor element by inserting the pivot shaft i4 alternately throughopenings l3 in the discs H and through the eyes IS in the shanks l5.With the rotor element rotated to the position illustrated in Figures 6and '7, wherein the hammers may extend vertically from the rotor elementwith the hammer head 2| uppermost, the pivot shaft I4 is movedlongitudinally of the rotor element to bring the several notches 35 intoregistry with the longitudinal bores 22 in the shanks l5. In thisposition the inner end of each locking pin 23 drops into one of thenotches 35, thus clearing the slot I! in the outer end of the shank forinsertion of the key 32. Thereupon the hammer head 2| is placed on theshank, the end of the shank being received in the recess 26 with theslot H in the end of the shank aligned with the slots 3| in the sidewalls 28 of the head. Thereupon the key 32 is inserted in the alignedslots 3| and I1 and aeeaare the locking pin 23 is moved longitudinallyoi the bore 22 and caused to engage through the hole 33 in the key 32.This movement of the locking pin causes the inner end of the pin todisengage the notch 35 in the pivot shaft, whereupon the pivot shaft i imay be moved into the position shown in Figure 6, in which position theinner end of the locking pin 23 rides upon the outer surface of theshaft it and is prevented from dis engaging the key 32. The shaft it maybe secured in the final assembled position by means of a screw 35extending diametrically from the periphery of the outer disc it into theregistering notch 35 in the pivot shaft it.

' At such times as the hammer heads are to be reversed or replaced, orat the time of the initial assembly of the machine, the rotor elementmight well be rotated to he position shown in Figures 6 and '7 to permitthe hammers to extend vertically from the upper side thereof with theheads 2i in the uppermost position. Thereupon the screw 35 is withdrawnfrom engagement with the outermost notch 35 and the pivot shaft it ismoved longitudinally of the rotor element to place the notches 35 inregistry with the longitudinal bores 22 in the several shanks i5. Whenthis occurs the locking pins 23 drop into the notches 35 and disengagethe keys 32 which may then be removed from the aligned slots 3! and iiito release the hammer heads. The hammer heads may then be eitherreversed or replaced as required. When the hammers have been reassembledand the key 32 shall have been reinserted in the aligned slots 39 andi'i, the rotor element may be rotated through an angle of 180 degrees tocause the several locking pins 23 to drop into the hole 33 in the keyand disengage the several notches 35 in the pivot shaft it. Thereuponthe pivot shaft is moved longitudinally of the rotor element to disalignthe notches 35 and the longitudirial bores :22 in the shanks i and tobring the outermost notch 35 into registry with the screw 36 which isthen turned down to engage the notch to prevent longitudinal movement ofthe shaft during operation of the device.

Referring now to Figures 8 and 9, there is shown a portion of a rotorelement for a rotary crusher comprising spaced discs 37 and alongitudinally extending pivot shaft 38 as in the constructionhereinabove described. Mounted on the pivot shaft 35 is shown ahammerembodying the present invention. The hammer comprises a shank 393 havingan eye M provided in its inner end for the reception of the pivot shaft38', and an outer end portion 62 extending outwardly from shoulders #33.The outer end at of the shank is provided with a transverse slot 44disposed intermediate the plane of the shoulders 43 and the ex treme endsurface of the shank. The shank is provided with a longitudinal bore #35communicating at its outer end with the transverse "slot M. Mounted inthe longitudinal bore for free movement longitudinally thereof is alockin pin 46 adapted for engagement with the key 6? by means of whichthe hammer head 48 is secured to the shank.

The shank is provided intermediate its ends" which position the slots#36 and 56 are in alignment, the key il is inserted in the aligned slotsto secure-the head to the shank. The key Wis providedwith a center hole51? adapted to receive the end of the locking pin 66 to preventdisplacement of the key.

The locking pin 36 is of such length as to hear at one end against theouter wall 58 of the transverse slot it in the end of the shank, and tobear at the other end against a shoulder 59 on the screw plug 5i. Withthe key il inserted in the aligned slots i l and 56, the locking pin 66enters the hole 5? in the key ti and is held therein by the shoulder 59on the plug 5i. To release the key ii? the screw plug 5i is backed upsufliciently to withdraw the shoulder 59 from the longitudinal bore #35,whereupon the locking pin (it may drop out of engagement with the key itto permit removal or the key from the aligned slots 63 and 55, thusreleasingthe head M The locking pin 38 is chamfered at its outer end toprovide a shoulder ti by which the pin may be engaged to withdraw itfrom engagement with the key in the event an accumulation of dust orother matter may tend to plug the longitudinal bore :35.

in the manufacture or the hammers shown in Figures 8 and9, the shank 39is cast with the longitudinal bore 45 extending from the eye 5H in theinner end of the shank to the transverse slot tli in the outer end ofthe shank, the longitudinal bore communicating with both the eye ii andthe slot it. It will be noted that the length of the locking pin 416 isslightly less than the diameter of the eye-til, and in assembling theshank the locking pin is inserted in the longitudinal bore 45 throughthe end thereof which communicates with the eye 6 i. Thereupon thelongitudinal bore 65 is plugged at the point of its intersection withthe transverse bore 39, as by means of a plug S2, for preventing loss ofthe locking pin from the longitudinal bore by way of the eye iii. Thelocking pin is of lesser diameter than the longitudinal bore 65 and ispermitted free longitudinal movement therein, being retained therein bymeans of the plug 62 intermediate the length of the bore, and by the endportion of the shank forming the outer wall of the transverse slot dd.

To reverse or replace a head 48 on a shank 39 the plug 5| is unscrewedfrom the threads in the end of the transverse bore 49 a suflicientdistance to clear the pin 46, whereupon an appropriate tool, or even afinger, may be inserted into the opposite end of the transverse bore $9to engage under the shoulder 6! on the pin 35 to withdraw the pin fromthe hole 51 in the key 81. If convenient, the rotor element may berotated to the position illustrated in Figures 8 and 9 to permit thehammers to extend vertically from the upper side thereof with the headsas in the uppermost position. In such position, when the plug 5| isbacked out of the transverse bore 49 the locking pin 46 will drop out ofengagement with the key 81 and the key be thereupon removable to releasethe head as shown in Figure 9. When the head shall have been re- 7versed orreplaced and the key reinserted in position to engage thealigned slots 44 and 56, the locking pin may be moved to extend throughthe hole 51 in the key and the plug II threaded into 'the transversebore 49 to retain the pin in looking engagement with the key.

- An important advantage of the invention is that it precludes thenecessity of disconnecting the shank portion of the hammer from therotor element when reversing or replacing the head, which permits suchrepairs to.be made within a minimum period of time and without the useof special tools. A further advantage is that no strain is placed on thelocking pin during operation of the crusher, the resulting stressesbeing absorbed by the key member which locks the head on the shank.

There is herein shown and described a particular embodiment of theinvention,- illustrating the principle thereof as applied to a hammerfor impact crushers. It will be understood, however, that the inventionis applicable to other structures embodying a. releasable fasteningmeans for a detachable part, and that various changes in form,proportion, size and details of construction to without departing fromthe spirit or sacrificing any of the advantages of the invention.

Having now described my invention and in what manner the same may beused, what I claim as new and desire to protect by Letters Patent is:

1. A hammer for impact crushers comprising a shank, a hammer headreplaceably mounted on the end of said shank, said shank comprising aninner end having an eye therethrough for mounting said shank on thepivot shaft of a rotor element in a rotary crusher and an outer endhaving a slot extending therethrough, a bore extending longitudinally ofsaid shank and opening into said slot, a locking pin disposed in saidbore and having free movement longitudinally thereof, the headcomprising a work performing portion positioned away from the shank, ashank and receiving portion positioned toward the shank. a central openrecess within said latter portion of such size as to receive therein theouter end of said shank, said recess having opposite wall portions,aligned slots extending through said wall portions, the slot in theouter end of said shank being in alignment with the slots in said wallswhen said shank and head are in assembled relation, '8. key insertableinto the opening formed by said slots for locking said head on saidshank, a through hole in said key for receiving the end of said lockingpin when said key is in said opening, and means movable into engagementwith the opposite end of said pin for releasably holding said pinin-engagement with said key.

2. A centrifugal hammer comprising a shank, means adjacent one end ofsaid shank for mounting said shank on the rotor element of a rotarycrusher, means defining a slot extending through said shank adjacent theopposite end thereof, a bore extending longitudinally of said shank andopening into said slot, a locking pin disposed in said bore and beingmovable longitudinally thereof, a hammer head replaceably mounted on theslotted end of said shank comprising a work performing portionpositioned away from the shank, a shank end receiving portion positionedtoward the shank, a central open recess within said latter portion forreceiving therein in closely fitting engagement therewith the slottedend of said shank, said recess having opposite wall por- 'tions, alignedslots extending through said wall portions, the slot in the end of saidshank being in alignment with the slots in said walls when the shank andhead are in assembled relation, a key insertable into the opening formedby said slots for locking said head on said shank, said locking pinbeing movable into locking engagement with said key when said key is insaid opening, and means for releasably holding said pin in engagementwith said key.

3. A centrifugal hammer comprising a shank and a'hammer head replaceablymounted on said shank, upstanding walls on said head defining a recesstherebetween, means defining aligned openings extending through saidwalls, said shank comprising an end portion adapted to be received insaid recess between said walls, means defining an opening through thehead engaging portion of said shank, a bore disposed longitudinally ofsaid shank extending into said opening, the opening in said shank beingin alignment with the opening in said walls when said shank and head arein assembled relation, a key insertable into the opening through saidassembled g5 shank and head for locking said head on said within thescope of the claims may be resorted shank, and a pin slidably mounted insaid bore and movable into the opening in said shank for engaging saidkey, and means for releasably holding said pin in engagement with saidkey.

4. A centrifugal hammer comprising a shank member and a head memberreplaceabiy mounted thereon, a coupling for detachably locking saidmembers in operative relation, said coupling comprising upstanding wallson one of said members defining a recess therebetween, aligned openingsextending through said walls, a portion of the other of said membersadapted to be received in said recess between said walls and having anopening extending therethrough, the openings in both said members beingin alignment when said members are in assembled relation, a keyinsertable into said openings, and means carried by said shank memberand movable into engagement with said key for releasably holding saidkey in said openings, said means being shrouded by said shank member andslidable therewithin for movement between positions of engagement anddisengagement with said key.

5. A coupling means for detachably coupling separable parts in unitedoperative relation, comprising a part having upstanding walls defining arecess, aligned openings extending through said walls, a second parthaving an end portion adapted to be received in said recess and havingan opening extending therethrough, a bore in said second part extendinginto said opening, the opening in said second part being in alignmentwith the openings in said walls when said parts are in assembledoperative relation, a key insertable into the opening through saidassembled parts for locking said parts in operative relation, and a pinslidably mounted in said bore and movable into engagement with said keyfor releasably holding said key in said locking position.

6. In a rotary crusher, a rotor element havin a shaft, a plurality ofhammers mounted on said shaft, each said hammer comprising a shank and ahead replaceably mounted on said shank, said shank and said head havinginterengaging parts for mounting said head on said shank, means definingopenings through each of said interengaging parts, said openings beingin alignment when said shank and head are mounted in operative relation,a key insertable in said openinks for detachably locking said head onsaid shank, means mounted in said shank for holdin said key in saidaligned openings, and means mounted in said shank for releasably holdingsaid last named means in engagement with said key. I

7. In a rotary crusher, a rotor element having a shaft, a plurality ofhammers mounted on said shaft, each said hammer comprising a shank and ahead replaceably mounted on said shank, said shank and said head havinginterengaging parts for mounting said head on said shank, means definingopenings through each of said interengaging parts, said openings beingin alignment when said shank and head are mounted in operative relation,9. key insertable in said openings for detachably locking said head onsaid" shank, a pin mounted in said shank for holding said key in saidaligned openings, and means mounted in said shank for releasably holdingsaid pin in engagement with said key.

8. In a rotary crusher, a rotor element having a. shaft, a plurality ofhammers mounted on said shaft, each said hammer comprising a shank and ahead replaceably mounted on said shank, said shank and said head havinginterengaging parts for mounting said head on said shank, means definingopenings through each of said interengaging parts, said openings beingin alignment when said shank and-head are mounted in operative relation,a key insertable in said openings for locking said headon said shank, apin mounted in said shank for holding said key in said aligned openings,and means defining a recess in said shaft into which said pin may bemoved to release said key, said shaft being movable relative to saidrotor element to move the recess in said-shaft into alignment with saidpin.

9. In a. rotary crusher, a rotor element having a shaft, a plurality ofhammers mounted on said shaft, each said hammer comprising a shank and ahead replaceably mounted on said shank, said 10 shank and said headhaving inter-engaging parts for mounting said head on said shank, meansdefining openings through each of said interengaging parts, saidopenings being in alignment when said shank and head are mounted inoperative relation, a key insertable in said openings for locking saidhead on said shank, a bore extending longitudinally of said shank andcommunicating with the shank opening'into which the key is inserted, anda pin slidably mounted in said bore and movable into interengagementwith said key, and means for releasably holding said pin in lookingposition.

10. In a rotary crusher, a hammer shank, a hammer head, a key engagingsaidhead and said shank for detachably mounting said head on said shank,and a smooth locking pin slidable in a longitudinal bore in said shankinto interengagement with said key for locking said head on said shank,and also slidable in said bore for releasing said key without removal ofthe pin.

' LESLIE G. EHMANN.

' REFERENCES CITED The following references are of record in the file ofthis patent:

UNI'I'ED STATES PATENTS Number Name Date 848,273 Travis Mar. 26, 19071,170,370 Wald Feb. 1, 1916 1,618,826 Hiller Feb.,22, 1927 1,693,058Shelton Nov. 27, 1928 2,170,407 Hartshorn Aug. 22, 1939 2,186,047 StineJan. 9, 1940 FOREIGN PATENTS Number Country Date 666,162 Germany Oct.11, 1938 671,397 Germany Feb. 6, 1939 683,171 Germany Oct. 31, 1939

